Optional. A description of the icon used for accessibility. If unspecified, the default value Button is provided. As a best practice, you should set a helpful description for what the icon displays, and if applicable, what it does. For example, A user's account portrait, or Opens a new browser tab and navigates to the Google Chat developer
documentation at https://developers.google.com/workspace/chat.
If the icon is set in a Button, the altText appears as helper text when the user hovers over the button. However, if the button also sets text, the icon's altText is ignored.
The crop style applied to the image. In some cases, applying a CIRCLE crop causes the image to be drawn larger than a built-in icon.
The icon displayed in the widget on the card. The following is a list of mutually exclusive fields. At most one of the fields will be set in a response:
knownIcon
string
Display one of the built-in icons provided by Google Workspace.
For example, to display an airplane icon, specify AIRPLANE. For a bus, specify BUS.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2026-11-06 UTC."],[],[]]